Brad Pitt never gets the credit he deserves for his acting because he's a pretty boy and the press is a lot more interested about how he and Jennifer are doing. That's a shame because he is a talented actor that isn't afraid to take chances with both the roles that he picks and the characters that he plays. That is quite rare in the A-list world. Morgan Freeman is a great actor. You can always count on him to do what he does best which is play a wise veteran that has seen it all. Kevin Spacey is another great actor that has great range and really puts life and personality into his characters.
The real talent of this movie, excluding the actors that brought it to life, is the director David Fincher and the writer Andrew Kevin Walker. Fincher's talents for making a visually stunning film are now well known and he often brings a dark patina to his work. Andrew Kevin Walker must have some incredible demons living inside him. Either that or one hell of an imagination for bringing the intricate story of Seven and the plan of John Doe to life.
John Doe's plan really is twisted and I won't be spoiling it here. Suffice to say I have never seen so evil and complicated a plan in a movie before or since. The cinematography of the film is dark but beautiful and throughout the film it is either night or raining or both except for two very brief moments. It is such an emotional movie that you can't keep from being caught up in what is happening. Do you understand and sympathize with what John Doe is doing or do you think him a mad killer that must be stopped.